1. Field of the Invention
This invention relates generally to wet photographic film printers, and more particularly to wet photographic film printers suitable for reproducing commercial quality movie film in large quantities.
2. Description of the Prior Art
Wet photographic film printers which use a printing head immersed in a liquid having an index of refraction very close to that of the printing negative are well known in the art. The wet printing process is effective to "fill in" and thus obscure scratches and abrasions on the negative so they do not appear in the final printed film. A variety of suitable liquids are known and several preferred liquids are set forth in an article entitled "Printing Motion Picture Film Immersed in a Liquid" published in the Journal of the Society of Motion Pictures and Television Engineers, October 1957 issue, Volume 66, pp. 607-615 hereby expressly incorporated by reference herein. A variety of different wet printers have been devised, such as those discussed in the article "Specifically Designed Total-Immersion Liquid Gate Printers" (March, 1974 Journal of the SMPTE, Volume 83, pages 163-169); however, the prior art has generally taken the form of continuous contact type liquid immersion printers such as are shown in U.S. Pat. Nos. 4,105,329 issued to Carter, 3,664,738 issued to Cameron, and 3,488,121 issued to Dassonville.
A number of difficulties have developed in connection with liquid immersion printers. The immersion of the raw stock and master and the high speeds that are involved often result in turbulence in the liquid which shows up as distortion in the printed film. In addition, after continued use dirt and other particulate matter tends to collect within the tank which can also distort the printed image. It is also necessary to remove the liquid from the film after printing. Because of the high speeds involved effective removal of the liquid is often a problem. In addition, the fumes generated by the immersion liquid are usually noxious resulting in some hazard to machine operators. Finally, the wet printers are generally incompatible with dry printing set-ups. Thus, those who wish to wet print must purchase an entirely new printing system at considerable expense.